1. Technical Field
The disclosure relates to an electronic component mounting structure.
2. Related Art
In recent years, there has been a great desire for increasing mounting density of the electronic component mounting structure in which an electronic component such as a semiconductor chip is mounted.
As a technique for increasing mounting density of the component, there has been disclosed a three-dimensional electronic circuit substrate in which an electronic component is mounted in a hollow portion provided on a side surface, and a plurality of circuit substrates is connected through a relay substrate on which lead-out wiring is formed on upper and lower surfaces thereof (see JP 4046088 B1, for example).